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1.
己酮可可碱预处理对大鼠供肝冷缺血损伤影响的实验研究   总被引:1,自引:0,他引:1  
目的 探讨已酮可可碱预处理供者及肝脏对供肝冷缺血损伤的影响。方法 Wistar大鼠按处理方法的不同分为 4组 :对照组、供者预处理组 (实验 1组 )、供肝预处理组 (实验 2组 )、供者及供肝联合预处理组 (实验 3组 ) ,预处理使用己酮可可碱。各组动物均在供肝冷保存 6h后行原位肝移植 ,门静脉血流恢复后第 30min、3h及 2 4h取门静脉血测定肿瘤坏死因子 (TNF α)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶 (AST)及谷胱甘肽S转移酶 (GST)的水平。结果 门静脉复流后 30min、3h时血清TNF α水平 ,各实验组明显低于对照组 ,实验 3组显著低于实验 1组及实验 2组 (P <0 .0 5) ;30min及 3h时血清GST水平 ,各实验组明显低于对照组 (P <0 .0 5) ,实验 3组显著低于实验 1组及实验 2组 (P <0 .0 5) ;30min及 3h时血清ALT水平 ,各实验组明显低于对照组 ,实验 3组显著低于实验1组及实验 2组 (P <0 .0 5) ;2 4h时前述各指标各实验组明显低于对照组 ,实验 3组显著低于实验 2组 (P <0 .0 5) ;30min时血清AST水平 ,各实验组明显低于对照组 ,实验 3组显著低于实验 1组及实验 2组 (P <0 .0 5)。结论 己酮可可碱预处理对供肝的冷缺血再灌注损伤有一定的保护作用  相似文献   
2.
Objective: To investigate whether pentoxifylline could play a role in attenuation of the hazardous effects of ischemia/reperfusion on corporeal tissue in a rat model of veno-occlusive priapism (VOP). Materials and methods: Placebo and pentoxifylline were given to eight groups of rats prior to priapism being induced by a vacuum constrictive device for durations of 6 and 12 h, respectively. Half of the groups of rats that underwent the same duration of priapism (ischemic) were subjected to 1 h of detumescence after band removal (reperfusion). One group underwent no manipulation and no drug administration and served as a baseline determination (control). Corporeal homogenates were examined for lipid peroxidation (LP) derived malondialdehyde (MDA) accumulation via thiobarbituric acid assay. Results: MDA concentration differed significantly between VOP rats and controls (P < 0.001) but did not differ significantly between ischemic-only groups and reperfused groups (P > 0.05). In the pentoxifyllinepretreated groups, although MDA accumulation tended to be slightly lower than in the placebo groups, the difference was not statistically significant (P > 0.05) either in the 6- or 12-h duration priapic groups. Conclusions: LP, an indicator of radical oxygen metabolite (ROM) induced injury, occurs in rat corporeal tissue during and after abolishment of VOP. Single-dose pentoxifylline pretreatment failed to exert a protective effect on corporeal tissue in a rat model of VOP in terms of attenuation of LP.  相似文献   
3.
已酮可可碱对神经病理性疼痛大鼠的镇痛作用及机制   总被引:1,自引:1,他引:0  
目的观察已酮可可碱(PTX)对神经病理性疼痛大鼠的镇痛作用及其机制。方法成年雄性SD大鼠96只随机分为假手术组、慢性坐骨神经结扎损伤(CCI)组和PTX组,CCI组和PTX组按Bennett法建立CCI模型.PTX组于术前1d开始至取材点每天腹腔注射PTX 100mg/kg.假手术组注射相同容积的生理盐水,CCI组造模后不做任何处理。于手术后1、3、7、11、14、21d用von-Frey filaments测定机械性痛觉过敏(MWT),按Hargreaves法测定热痛觉过敏(TWL);并于1、7、14、21d时处死大鼠,取腰段脊髓用双抗体夹心ELISA法测定细胞因子含量。结果与假手术组相比,CCI模型大鼠机械痛阈于术后1d开始下降,7d最显著,热痛阈3d时下降最显著(P〈0.01)。PTX组痛阈在各时间点均较CCI组显著升高(P〈0.05)。CCI后1d即出现IL-6、TNFα、IL-1β蛋白含量升高,于术后7d达到高峰,14d时仍然较高(p〈0.05)。TNFα和IL-1β于术后21d明显下降至接近基础值,但IL-6表达一直持续至术后21d。PTX组脊髓细胞因子含量明显低于CCI组(P〈0.05)。结论PTX可显著抑制神经病理性疼痛,此作用与其抑制脊髓细胞因子表达有关。  相似文献   
4.
目的探讨高压电烧伤对家兔血液流变学的影响及已酮可可碱对血液流变学异常的改善作用。方法将40只家兔随机分为高压电烧伤组(电伤组)、高压电烧伤复合已酮可可碱治疗组(复合组),每组20只。采用BV-100型悬丝生物流变仪,检测两组家兔伤前1 h、伤后即刻、伤后24 h、伤后48 h共四个时相的血液流变学指标,指标包括全血黏度(ηb)、全血还原黏度(ηr)、血浆黏度(ηp)、血沉(ESR)、血沉方程K值(K)、红细胞比容(HCT)、纤维蛋白原(FB)、红细胞聚集指数(EAI)、红细胞刚性指数(TK),对检测结果进行统计学分析。结果1、组内比较:电伤组和复合组ηb、ηr和EAI伤后各时相值均较伤前1 h升高(P<0.05);ηp、ESR、K、HCT、FB均从伤后24 h升高,24、48 h与伤前1 h比较均有显著性差异(P<0.05);电伤组TK于24、48 h升高,与伤前1 h比较均有显著性差异,而复合组TK伤后各时相与伤前比较无显著性差异(P>0.05)。2、组间同时相比较:复合组伤后各时相ηb和ηr均低于电伤组(P<0.05);复合组伤后24、48 h两个时相的ηp、ESR、K、HCT、FB、EAI、TK均低于电伤组(P<0.05)。结论高压电烧伤可引起家兔血液流变学异常,已酮可可碱对高压电引起的血液流变学异常有改善作用。  相似文献   
5.
Pentoxifylline, a non-specific cytokine inhibitor, has shown to be beneficial in inflammatory pain in both experimental and clinical studies. The present study demonstrates for the first time, to our knowledge, the antihyperalgesic effect of pentoxifylline in the neuropathic pain using L5 spinal nerve transection rat model. In a preventive paradigm, pentoxifylline (12.5, 25, 50, or 100 mg/kg intraperitoneally) was administered systemically daily, beginning 1 h prior to nerve transection. Pentoxifylline (50, or 100 mg/kg i.p.) produced significant decrease in the mechanical and thermal hyperalgesia. However, pentoxifylline (100 mg/kg i.p.) did not influence the paw pressure thresholds and paw withdrawal latency in sham-operated rats. In order to understand the possible antinocicieptive effect of pentoxifylline in neuropathic pain, we examined the level of TNFα, IL-1β, IL-6 and IL-10 protein in the contralateral brain on day 7 post-transection. Pentoxifylline administration resulted in a dose-dependent reduction of the production of proinflammatory cytokines like TNFα, IL-1β and IL-6, and enhancement of IL-10. Furthermore, we investigated the activity of nuclear factor kappa B (NF-κB) in the contralateral brain on days 7 after surgery. In accordance with the change of proinflammatory cytokines, Pentoxifylline (50 or 100 mg/kg) significantly inhibited the activation of NF-κB in the brain. This research supports a growing body of literature emphasizing the importance of neuroinflammation and neuroimmune activation in the development of neuropathic pain states, and the potential preventive value of pentoxifylline in the treatment of neuropathic pain.  相似文献   
6.
高糖及己酮可可碱对肾间质成纤维细胞作用的研究   总被引:1,自引:0,他引:1  
目的:探讨糖尿病肾病肾间质病变的机理以及己酮可可碱对肾间质成纤维细胞的作用。方法:为研究高糖对肾间质成纤维细胞的作用,应用MTT比色法检测细胞的增殖,应用流式细胞仪检测细胞周期变化,并应用ELISA法检测细胞上清液中的纤维连接蛋白。同时,本研究也观察了己酮可可碱(Pentoxifylline),一种非选择性的磷酸二酯酶抑制剂对肾间质成纤维细胞的作用。结果:高糖和己酮可可碱均可抑制细胞增殖,影响细胞周期,但高糖可促进成纤维细胞分泌细胞外基质纤维连接蛋白,而己酮可可碱可减少其分泌,且可抑制高糖对成纤维细胞的作用。结论:高糖可能通过促进肾间质成纤维细胞分泌细胞外基质在糖尿病肾病的间质病变中起作用。而己酮可可碱抑制细胞增殖及细胞外基质的分泌将有利于肾间质病变的防治。  相似文献   
7.
We compared the efficacy of oral administration of pentoxifylline (PTX) and intravenous infusions of gamma globulin (IVGG) combination therapy with that of IVGG in reducing the frequency of coronary-artery lesions (CAL) in children with Kawasaki disease (KD), in a randomized trial. All patients with KD received acetylsalicylic acid (30 mg/kg per day), until the 30th day, after the onset of fever, followed by daily acetylsalicylic acid at a dose of 3-5 mg/kg per day there-after, and intravenous IVGG, 200 mg/kg per day, for 5 consecutive days. In addition, patients randomly assigned to PTX and IVGG combination therapy groups received oral PTX at a dosage of 10 mg/kg per day (low-dose) or 20 mg/kg per day (high-dose), in three divided doses until the 30th day. Patients with KD were all free from CAL prior to treatment. We assessed the presence of CAL by two-dimensional echocardiography which was also done prior to treatment and then twice a week after hospital admission. We detected CAL in 3 of 18 patients (16.7%) in the IVGG therapy group, as compared with 2 of 18 patients (11.1%) in the low-dose PTX and IVGG combination therapy group. There were no significant differences between the two groups. In the next study, we detected CAL in 3 of 21 patients (14.3%) in the IVGG therapy group, as compared with none of 22 patients (0%) in the high-dose PTX and IVGG combination therapy group (2 = 6.4, P < 0.02). No adverse side-effects were observed in 79 patients with KD.  相似文献   
8.
Increased plasma tumour necrosis factor (TNF) concentration correlates with mortality in sepsis. We suggested that pentoxifylline (PTXF), which is known to inhibit TNF production, may improve survival and attenuate clinical symptoms of sepsis in neonates. Plasma TNF levels were evaluated in 29 newborn infants with sepsis. Patients were randomly assigned into two groups, receiving PTXF in a dose of 5 mg/kg per hour for 6 h or placebo (saline), on 3 successive days. Both groups were subjected to the same conventional therapy. TNF was evaluated before and after PTXF or placebo administration on the 1 st and 3rd days of therapy. There was a statistically significant decrease in plasma TNF level in the PTXF group when the values before the first and after the last PTXF infusion were compared [mean: 671.5 pg/ml; SD: 438; med: 729.6 vs mean: 41.0 pg/ml; SD: 64.1; med: 11.5;P<0.000004]. In the placebo group, decrease was not significant [mean: 633.0 pg/ml SD: 488.6; med: 618.9 vs 246.9 pg/ml; SD: 243.9; med: 191.0]. A significantly higher plasma TNF level, evaluated after the last PTXF infusion, was found in the placebo group [246,9 pg/ml vs 41.0 pg/ml;P<0.001]. Only one of four infants with signs of shock in the placebo group survived, whereas all of five newborns with symptoms of shock in the PTXF group survived [P<0.04]. An increased incidence of metabolic acidosis [P<0.05], necrotizing enterocolitis [P<0.04] and renal insufficiency [P<0.05] was observed in infants in the placebo group.Conclusion PTXF inhibits production of TNF and may have therapeutic value in the treatment of premature infants with sepsis complicatea by shock.  相似文献   
9.
目的观察不同时间给予己酮可可碱(pentoxifylline,PTX)对新生大鼠缺氧缺血性脑损伤(hypoxic-ischemic brain damage,HIBD)模型的影响。方法建立新生大鼠HIBD模型,120只出生7 d的wistar大鼠随机分为假手术(Sham)组、HIBD模型组和3种PTX(50 mg/kg腹腔注射)给药组,即缺血末均给药(I PTX)组、缺氧末给药(H PTX)组及缺血和缺氧末均给药(I,H PTX)组,各组均于缺血缺氧处理后72 h取出左脑,测定脑组织水含量、大脑皮层神经组织游离钙离子浓度、超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮合酶(NOS)及一氧化氮(NO)。结果HIBD模型组与Sham组相比,脑组织含水量、游离钙离子浓度、MDA、NOS及NO水平显著升高(均P<0.01),SOD水平明显降低(P<0.01)。3种PTX给药组与HIBD模型组相比,脑组织含水量、游离钙离子浓度、MDA、NOS及NO水平均显著降低(均P<0.01),SOD水平明显升高(P<0.01)。以上作用尤以(I,H PTX)组明显。结论 PTX对新生大鼠缺氧缺血后脑组织有保护作用,其机制可能与PTX改善能量代谢及减少局部细胞毒性物质有关。  相似文献   
10.
目的探讨己酮可可碱(pentoxifylline,PTX)在大容量机械通气诱导的大白鼠肺损伤炎性反应中的作用。方法大白鼠在接受4h大容量机械通气时,治疗组(8只)静脉给予PTX,对照组(15只)静脉给予生理盐水,比较通气前后气道灌洗液中血栓烷B2(thromboxane B2,TXB2)、肿瘤坏死因子α(tumor necrosis factor-alpha,TNF-α)、血小板活性因子(platelet activating factor,PAF)、肺组织髓过氧化物酶(myeloperoxidase,MPO)水平和肺组织湿干重量比。结果气道灌洗液中TXB2治疗组通气前为(17±4)ng/L,通气后为(13±1)ng/L,对照组通气前为(15±2)ng/L,通气后为(21±2)ng/L,两组通气后比较差异有统计学意义(P<0.01);TNF-α治疗组通气前为(39±19)ng/L,通气后为(245±76)ng/L,对照组通气前为(29±16)ng/L通气后为(620±112)ng/L,两组通气后比较差异有统计学意义(P<0.01);PAF两组通气后比较差异无统计学意义。治疗组肺组织MPO为(0.6±0.1)OD/g,对照组为(1.4±0.7)OD/g(P<0.01);治疗组肺组织湿干重量比为(6.3±0.3)g/g,对照组为(7.3±0.4)g/g(P<0.01)。结论PTX在抑制大容量机械通气诱导大白鼠肺损伤的炎性反应中有一定的积极作用。  相似文献   
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